This Interagency Agreement provides funding from the National Institute of Aging (NIA), National Institutes of Health (NIH) to the U.S. Agency for International Development (USAID). Through USAID, NIA will provide funds to support the following activity. The intent of this initiative is to enhance and expand the program of demographic surveillance through the International Network of field sites with continuous Demographic Evaluation of Populations and Their Health in developing countries (INDEPTH). This initiative will focus on the impact of HIV/AIDS within the community and at the household level, with emphasis on the health, economic status, and well being of older adults. Through USAID, NIA will provide funds to Information, Evidence and Research Program to be used by the Multi-country Studies Project in Health Statistics and Informatics. Through this project, WHO will support a network of INDEPTH Asian and African demographic surveillance sites in collaboration with the Study of Global AGEing and Adult Health (SAGE) for continuation and expansion of existing monitoring to measure the impact of HIV/AIDS within communities and households in the surveillance communities. Specifically, in collaboration with NIA and other agencies, this initiative will support training, questionnaire module expansion and harmonization, data collection, and analysis including microsimulations.